1. The general aim of this proposal is to realize the scientific potential of the newly formed Pediatric Oncology Group (POG). Investigators at Oklahoma will continue our research in oncology by registering patients on POG and intergroup protocols, to continue to write protocols for POG, to continue to pilot protocols, and to continue to analyze data and generate manuscripts and abstracts. Specific activities of investigators at Oklahoma done for POG include; 2. To continue to redefine subgroups within acute lymphoblastic leukemia (ALL) that have prognostic significance. We will periodically analyze acummulating data from our tumor marker studies (ALinC 13). The following need to be periodically analyzed: the prognostic significance of a complement receptor on null and pre B cells, the thermal stability of the E receptor and T cell ALL, the relative prognostic significance of T antigen positive and E receptor positive T ALL, the significance at diagnosis of circulating normal T cells or activated T cells in null cell and pre B cell ALL, etc. 3. To attempt to improve the therapeutic outcome and better define central nervous system tumors by evaluating the therapeutic efficacy of cis-platinum and by studying tumor markers such as polyamines. 4. To attempt to apply tumor biology to human solid tumors in order to better define prognostic subgroups, to predict metastatic potential, etc. This involves a feasibility study to determine if solid tumors from member institutions can be mailed to Oklahoma for dissociation and cryopreservation in order to establish a solid tumor bank. 5. To increase the role of bone marrow transplantation in the management of leukemic children who have a poor prognosis. This will include not only sibling transplants but a program for parent to child bone marrow transplantation, initially for leukemic cases at Oklahoma and then as a POG protocol. 6. To establish a more accurate method of diagnosing meningeal leukemia using TdT. 7. A comprehensive evaluation of all stages of neuroblastoma. 8. To determine if viral infections at the time of diagnosis have prognostic significance with regard to immunosuppressive viruses such as CMV and EBV. 9. To provide leadership and serve the administrative needs of POG. Investigators at Oklahoma are involved in a number of scientific and administrative committees for POG.